Power-on-reset (POR) circuits typically provide a control signal that keeps processing circuits idle as a power supply powers up and then changes a state of the control signal when the power supply output reaches a minimum voltage. POR circuits are used to assure that upon initial start-up of a device, processing circuits of the device responsive to the control signal begin their respective function in known states. Without a POR circuit, it can be possible for some processing circuitry to begin processing at different times than other processing circuitry because some processing circuitry can become active at a lower supply voltage than other processing circuitry. Such a situation can allow some circuitry to begin processing signals from other circuitry, however, the signals may not be valid. Add in a supply glitch on power up, for example from some processing circuitry starting before other circuitry, and the initial state of a device can become unpredictable. However, adding a POR circuit also adds power consumption and circuit space that can limit other resources or characteristics of a device.